Method of distilling and condensing.



No. 808,649. PATENTED JAN. 2, 1906. J. S. FORBES.

METHOD OF DISTILLING AND GONDENSING.

APPLICATION FILED AUG. 20, 1903.

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N0. 808,649. PATENTED JAN. 2, 1906 J. S. FORBES.

METHOD OF DISTILLING AND CONDENSING APPLICATION FILED AUG. 20, 1903.

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3. M, v -/07zm5 112F566- 5 @M Maw. wimvvd I in JOHN S. FORBES, OF PHILADELPHIA, PENNSYLVANIA.

METHOD OF DISTILLING AND CONDENSING.

Specification of Letters Patent.

Patented Jan. 2, 1906.

Application filed August 20, 1903. Serial No. 170,188.

To all whom, it may concern:

Be it known that 1, JOHN S. FORBES, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Methods of Distilling and Condensing, of which the following is a specification.

My invention relates to certain improvements in methods of treating liquid in order to secure from bodies of vapor and liquid a relatively large quantity of distilled liquid, and that at a relatively high efficiency of operation.

My improved method is particularly designed to be employed in connection with the condensation of exhaust-steam by means of a condenser employing water or other suitable liquid as a condensing agent, the steps of the process being so arranged that when water is the liquid treated there is added to the distilled or pure water resulting from the condensed steam a further quantity of distilled water obtained from the condensing water. My method is also equallywell adapt ed for concentrating various solutions.

The above-noted objects I secure as hereinafter set forth, reference being had to the accompanying drawings, in which Figure 1 is asectional elevation, largely diagrammatic, illustrating one arrangement of apparatus for carrying out my improved invention, the same being designed to operate with a surface condenser. Fig. 2 is a sec tional elevation of somewhat similar apparatus in which is employed a jet-condenser. Fig. 3 is a sectional elevation of a working arrangement of the apparatus shown in Fig. 1, and Fig. 4 is a sectional elevation showing a similar arrangement of the apparatus illustrated diagrammatically in Fig. 2.

In the above drawings, a is a pipe connected to the exhaust of an engine, or, if desired, to any other source of relatively low-pressure steam, and this pipe discharges into a casing A, in which is placed a serles of pipes a, which may be in the form of coils. or in any other of the arrangements common to surface condensers or evaporators. One end of this coil, in the present instance the upper end, is connected to a pump, (not shown,) which forces through it a constant current of condensing water or other liquid, and its other end discharges within and near the bottom of a casing B, which has connected to-its lower portion a pump 1) for removing the greater part of this liquid. A vapor-pump C has its inlet 0 connected to the upper portion of the casing B and its outlet 0 connected to the interior of the casing A, a third pump 1) serving to remove condensed liquid from the bottom of said latter casing.

In the form of my invention shown in Fig. 2 the steam-pipe a is connected directly to a head a, which contains a spraying device a of any of the forms common to jet-condensers. This, as usual, is connected to a source of supply for condensing liquid. A pipe a connects the lower portion of the head a to the pipes 0/ which are arranged in a manner similar to that shown in Fig. 1.

In operation steam from some source, as above indicated, is supplied in the form of apparatus shown in Fig. 1, for example, through the pipe a and coming in contact with the relatively cool surface of the pipes at within the casing A is condensed and falls to the bottom of said casing as distilled water. By this process the condensing water is heated up to a certain degree, and with the vapor-pump C in operation a certain portion of this heated water is vaporized and delivered under pressure by said pump into the casing A. This vapor, whose pressure and relative temperature is properly calculated with regard to the pressure and relative temperature of the steam, coming in through the pipe at like said steam is condensed by the relatively cool surfaces of the pipe 0/ and with the water condensed from the steam is removed by the pump 1).

The following is a typical example of the calculations necessary in designing the apparatus for carrying out my improved method of treating fluid. Let it be assumed that the method is to be applied in connection with a one-thousand-horsepower triple-ex ansion engine consuming fifteen pounds 0 water per indicated horse-power hour, the steampressure being one hundred and eighty pounds, the vacuum twenty-two inches, and the steam system of the engine requiring, as per the Navy regulations, one gallon of water per horse-power per twenty-four hours to replace that unavoidably lost by leakage or other waste. Let it be further assumed that the temperature of the condensing water is Fahrenheit, the discharge water is 127 Fahrenheitfand that the water from the condensed steam is 137 Fahrenheit. Let, now, as in S anglers Thermodynamics, g equal the heat 0 the liquid of the steam or water, r equal the heat of vaporization, t equal the temperature of the steam in degrees Fahrenheit, p

equal the pressure of the steam in pounds per square foot absolute, W equal the weight of water necessary to condense one pound of steam, g g ,q, equal the heat of the liquid of the steam or water at the temperatures t t .t and pressures 10 19 ,p respectively. As we need one gallon or 8.33 pounds of water to compensate for that lost per horsepower per twenty-four hours, the amount required per pound of steam used is Q4 Qs (1', being the heat of vaporization of water at the temperature 15 Now, as stated, 9 corresponds to 25 which at a twenty-two-inch vacuum is 152.4 Fahrenheit, 25 e uals 137, t equals 80, 25 e uals 127, and from Peabodys Steam Tab es (120.7+1007*105.2) 2 if W 32 95.1-48.09

"or W equals 218 pounds of water required per pound of steam condensed. We must evaporate .0232 pound of this water from each 21.8 pounds to supply the losses of the system, and to do this as economically as possible a vacuum should be carried in the cham ber B such that the evaporation of, this amount will reduce the temperature of the remainder to the temperature corresponding to the vacuum. Calling this i we have, if r be the heat of vaporization at this temperature, 21.8 (g g .0232 r and, solving this, we find g equals 94.1, 25 equals 126, and 1), equals 1.985 pounds per s uare inch, or 25.95 inches vacuum. The wor required to compress the steam from 25.95 inches vacuum to twenty-two inches vacuum in a condenser may be expressed as the difference in the heating of the steam under the two conditions, and for each pound of steam this will equal, (9 +13) (g +r In order to reduce this to horse-power, we have For extracting the cooling-water the horse- 1.108 II. P.

power necessary is found by multiplying the volume by the pressure in pounds per square foot and dividing this by the time in minutes and by thirty-three thousand or the horsepower equals 62.5XX33000 X 44 48211-1) If now one and three-fourths pounds of coal in which S e uals heating-surface in square feet, W e ua s pounds of water condensed per hour, equals heat of steam, ck equals constant, equals one hundred and eighty, T equals temperature of the steam, t equals mean temperature of the cooling water. Therefore the above condenser would require S 1.0232 X 15 X 1000 X 1128.4

In connection With'the above it Will be noted that the allowance of one and three fourths pounds of coal per horse-power per hour is sufficient to obviate the necessity for taking into consideration the efiiciency of the per pound of coal equals 1960 sq. ft.

um p It will be seen that by the abovedescribed operation the steam from the engine or other source of supply of the same is condensed, parting with its latent heat to the condensing water. This latter instead of being discharged to waste, as is commonly the case, is so treated that a certain portion'of the heat contained in it is recovered through the agency of the compressor-pump C. In addition to this advantage it will be noted that my improved method of treatment is particularly applicable to systems in which the water obtained from the condensed engine-exhaust is again delivered to theboiler. In practice it has been found that there is always a certain amount of the water originally supplied to the boilers which is lost through leakage at various points of the system using the same, so that the water obtained from the condensed exhaust steam is not equal in amount to that originally supplied to the boiler. By my improved method I am enabled by the use of the surface condenser and other apparatus above described to obtain in addition to the water recovered from the condensed steam an additional amount of distilled water, which may equal or, if desired, exceed the amount of the above-noted loss, which is usually allowed to be one gallon per twenty-four hours per horse-power. The

amount of water secured depends upon the proportioning of the compressor-pump, as well as upon the provision of the necessary extent of condensing-surface in the coils a.

In the case of the jet-condenser illustrated in Fig. 2 the water obtained from the condensed steam is mixed with the condensing water and both are delivered in a relatively heated condition to the casing B. With such arrangement the compressor-pump is necessarily larger and more powerful than that illustrated with the arrangement of apparatus shown in Fig. 1; but its action is similar to this latter, since in either case it exhausts the vapor from the hot water in the casing B and delivers it at a higher pressure and temperature into the casing A around the outside of the pipe a. Since the temperature of this compressed vapor is necessarily higher than that of the water within the pipe at, said pipe, as before, acts as a condensing-surface, so that the distilled water may be collected at the bottom of the casing A and removed by the pump 1).

While in the foregoing description I have referred to my improved method of treating fluids as applied to systems employing steam and water, it will be understood that it may be applied with advantage to the treatment of other fluids, as well as to systems whose ultimate object was different from that noted above.

I claim as my invention- 1. The method of treating fluids which consists in condensing a body of vapor from an external source of supply by means of a cooler-body of fluid, exhausting vapor from said fluid after it has been used for condensing, compressing said vapor and then condensing the same, substantially as described.

2. The method of treating fluid, the same consisting in raising the temperature of a body of liquid by causing it to condense a vapor, vaporizing and then compressing the vapor from a portion only of said heated fluid thereby raising the temperature of the vapor and condensing said vapor by bringing it into contact with surfaces at a relatively lower temperature, substantially as described.

3. The method of obtaining distilled water, the same consisting in continuously delivering steam to a container, condensing said steam by bringing it into contact with watercooled surfaces within said container, exhausting vapor from the vesselreceiving the said water, and compressing the vapor so obtained in the said first container thereby condensing said vapor, substantially as described.

4. The method of treating fluid, the same consisting in condensing within a container a body of vapor obtained from a source of supply external to the same, exhausting vapor from a vessel containing the liquid employed in condensing said first body of vapor, compressing the same, and condensing said compressed vapor within said first container, substantially as described.

5. The method of treating fluid, the same consisting in passing liquid through a series of pipes, heating said liquid, simultaneously condensing a body of vapor by bringing the same into contact with said pipes, exhausting vapor from the liquid after it has passed through said series of pipes, compressing said vapor and forcing it into contact with the outside surface of said pipes, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN S. FORBES.

Witnesses WILLIAM E. BRADLEY, Jos. H. KLEIN. 

